This invention relates to internal combustion engines, and more particularly to the anaerobic operation of an internal combustion engine.
Conventional engines generally can only operate efficiently when there is sufficient oxygen in the ambient air for aerobic combustion of the fuel. Thus, conventional internal combustion engines do not perform satisfactorily under certain oxygen-deficient conditions where it is desirable to use them. For example, when fighting fires in enclosed structures or mines, there may be insufficient oxygen (i.e. less than 17%) in the ambient air to operate conventional chain saws. These chain saws are desired to be used to cut holes in walls in enclosed structures or to cut conveyor belts or fell timbers in mines to prevent the propagation of fire to other sections of the mine. Also, in mine rescue operations, diesel engines are used to drive foam generators and to drive pumps for firefighting purposes. These engines also cannot operate satisfactorily under low oxygen conditions which may occur in the mine.